This invention relates to window assemblies and in particular to window assemblies for use in awning-type windows, particularly those of metal construction such as might be used in recreational vehicles, mobile homes and the like.
As described in my related U.S. Pat. No. 5,103,590 issued Apr. 14, 1992, (disclosure of which is incorporated by reference) the prior art has provided numerous forms of closure operators for awning windows and the like. One such prior art arrangement has a twin arm operator located in a fixed position in the center of the fixed frame at the bottom of the awning. Since the operator is fixed, the arms are not able to move upwardly or downwardly to accommodate the arcuate path of travel of the awning window as it moves between the open and closed positions; such fixed arms can only move outwardly in a generally horizontal plane. In order to accommodate the arcuate movement of the awning window, the rigid twin arms have riveted to them flexible steel extensions with a small wheel on each end which runs in a track which is fastened to the bottom frame of the awning. A problem with these flex steel extensions on the twin arms is that the amount of flexing is relatively limited and this only allows the awning to open to a maximum of about 20.degree. which has the effect of blocking the direct breeze from entering. Since the flexing movement of the steel extensions is limited, awning windows of substantial vertical dimension must be used in order to achieve a relatively shallow or flat arc of movement of the lower edge of the awning. Unfortunately, this arrangement does not permit the awning to be lifted up sufficiently to let direct breezes enter through the window. It would therefore be most desirable to provide a system enabling even relatively short awning windows to be lifted high, i.e. to open up to a very large angle to let the breezes in thereby to provide maximum ventilation. In summary, the twin arm operating arrangement previously known with the flex steel extensions can only be used with awning windows of a substantial height (vertical dimension) and yet at the same time the ventilating capability of such windows is very limited since the low degree of opening angle prevents direct breezes from entering.
My above-noted U.S. patent describes a window operator for a pivotally mounted window co-operable with a fixed window frame, the window operator comprising an operating mechanism mountable to said fixed window frame, and an elongated guide track adapted to extend along a marginal portion of the pivotally mounted window. The operating mechanism includes a rigid elongated arm means and means for effecting pivotal motion of said arm means, the arm means having motion transmitting means mounted to distal free end portions thereof, said motion transmitting means adapted to engage with said elongated guide track and to move therealong as the arm means are pivoted thereby to pivot the window between open and closed positions. The arm means comprises a pair of free-ended rigid arms adapted to pivot towards and away from one another in a first plane of movement to pivot the window between open and closed positions respectively, said motion transmitting means comprising a ball fixedly secured to the distal end of each of said arms, and said guide track being shaped to secure the balls therein while permitting free movement of the balls therealong. Each ball is secured directly to the distal end of each arm and the guide track includes an entrance slot sufficiently wide as to permit a predetermined Mount of angular motion of the arm relative thereto and hence of the window between the open and the closed positions.